The disclosed subject matter relates to a system and method for controlling a semi-closed power cycle system.
Certain power generation systems include a gas turbine engine configured to combust a mixture of fuel and compressed air to produce hot combustion gases. The combustion gases flow through a turbine to generate power for a load, such as an electric generator. Certain gas turbine engines include a combustor configured to operate with a fuel-lean mixture ratio. Accordingly, the quantity of compressed air fed into the combustor is greater than the quantity sufficient for complete combustion of the fuel. As a result, the exhaust gas from the combustor contains a significant quantity of oxygen.
Exhaust gas from certain power generation systems may be employed for secondary recovery of minerals, such as oil. In such systems, pressurized exhaust gas is directed into mineral deposits within the earth to increase oil pressure and/or to fracture geologic formations, thereby enhancing oil recovery. In addition, because the exhaust gas remains within the geologic formation, at least a portion of the carbon dioxide produced by the power generation system will be captured within the earth. Unfortunately, the oxygen within the exhaust gas may degrade and/or otherwise adversely affect the quality of the oil. Therefore, it may be desirable to substantially reduce the oxygen concentration of the exhaust gas from the gas turbine engine.